Custom Roof Rack Mounts

[cico7]

Nice job drafting, or whatever you want to call it...CAD? Looks good on paper.

[Matt]

lol thanks guys.

[Matt]

Ok back to the task at hand.... Good chance I'll still have to use my Thule load bars for the time being (although I love the direct mount idea). Here's another concept that i like for a few reasons:
1) Doubles the mounting bolts = stronger and a lot more work to remove
2) Wider foot print for the mounts
3) Don't need to drill hole through load bar = easier adjustments

Downside is about double the cost (due to material scrap mostly... can order in 1' or 3' sections and only need a 20" section to make 6 mounts). But then again i'm sure I'll have a few prototype pieces anyway... so even if i go with the 2" mounts I'll probably want to get the 3' material regardless for mistakes and modifications to the design.

[Doc in AZ]

Dude, you have to get away from square stuff. I make roof racks from round tube for a reason... drag coefficient. Make it a little smoother, trust me, you will see a Los in MPG try to minimize it... and make it appealing not just functional. And roof racks come in any size you want and even in irregular shapes.

http://www.facebook.com/media/set/?s...5811010&type=1

[Matt]

Doc, its all squared off for concept only. Once I chose a design I will then modify it for aerodynamics and aesthetics. There's no point in spending another 20-30 minutes on each model to make it look pretty.

Edit: and what do you think about the welded bracket idea? I was actually thinking that if I had you make those brackets then I could even forego making tall stanchions since the brackets would just need to extend about 3/4" below the bottom of the rack. Then I'd just machine some platforms out of steel to give the rack a level surface instead of the angled rail. Ill draw that up tonight after my bike ride.

[CmmdrDan]

Ok back to the task at hand.... Good chance I'll still have to use my Thule load bars for the time being (although I love the direct mount idea). Here's another concept that i like for a few reasons:
1) Doubles the mounting bolts = stronger and a lot more work to remove
2) Wider foot print for the mounts
3) Don't need to drill hole through load bar = easier adjustments

Downside is about double the cost (due to material scrap mostly... can order in 1' or 3' sections and only need a 20" section to make 6 mounts). But then again i'm sure I'll have a few prototype pieces anyway... so even if i go with the 2" mounts I'll probably want to get the 3' material regardless for mistakes and modifications to the design.

I dont think I'd do it this way. Would want a bolt through the rail so it doesn't slide back and forth. Unless you put a small weld or something.

[Matt]

Dan, it wouldn't be able to slide back and forth. Every Thule setup you can buy uses clamping force to retain the bars.... and I can far exceed the clamp force of every Thule mount I've used with the 2 3/8" bolts, so I'm positive there's enough there to hold it in place.

[CmmdrDan]

I forgot you were the engineer. Carry on!

[Matt]

LMAO that doesn't mean I'm perfect or that I know everything. As a matter of fact, being that I've worked both blue collar and white collar I can tell you that the best ideas I've heard for stuff like this usually come from the "shop" guys. And some of the dumbest ideas and designs I've ever heard have come from engineers who had a great GPA in college. So please, don't ever hesitate to question something I post.... there's a reason engineers work in "teams", the best solutions are seldom self derived.

Hence, this isn't a "how to" thread. I'm open to all suggestions / ideas / comments / etc because they will help improve the design.

[IamJEEP]

I agree with doc about the squareness( is that a word lol) of the design but, if you look at the oem uprights...........they are not what I would call, aero.